Commercial poultry producers have long had to deal with the problem of bacterial contamination of the processed birds. Poultry is especially susceptible to such contamination and is especially difficult to decontaminate due to the tendency of the bacteria to cling to the skin and feather follicles. Cross-contamination of processed birds often occurs in the chilling phase of the processing when the birds are transported in masse through a cold water treatment to lower the temperature of the eviscerated carcasses.
Some of the more common pathogenic bacteria observed in poultry are Salmonella, E. coli, L. monocytogenes, and C. JeJunt. Recent studies have shown that between 30%-50% of frozen or refrigerated chicken carcasses are contaminated to some extent with Salmonella bacteria. Salmonellosis, as a common and often serious gastrointestinal disorder results from consumption of contaminated meat, most often from poultry products. Approximately two million cases of salmonellosis are reported annually in the United States alone.
Efforts have been made in an attempt to reduce the presence of Salmonella and other bacteria from poultry carcasses. A summary of the recent efforts was published in the Journal of Applied Poultry Research and is appended to this application. Various methods were explored in these efforts, namely counter current scalding; addition of a bird wash at the end of the scalder; addition of 20 ppm chlorine to the bird wash in the picking room, the water in the transfer belt and the final wash; and addition of chlorine into the chill water.
As shown in the above-noted publication, none of these processes are successful in removing all pathogenic bacteria from the contaminated carcasses. A probable reason for the failure of previous efforts at decontamination is that a thin film of water often forms around the carcass during chilling operations. This film forms a barrier which prevents direct contact of the skin and feather follicles by the disinfectant. The end result is that bacteria remain on the carcass even after disinfection treatments. The contamination problem has degenerated to the point that regulatory agencies such as the USDA and FDA are considering the adoption of regulations which would require total irradiation of all poultry carcasses to destroy the bacteria and further prevent the spread of foodbourne diseases.